Typically, systems for performing biological analysis comprise a cartridge designed to hold the biological sample and comprise fluidic circuits to prepare and isolate the desired elements from the biological sample to perform specific analysis such as DNA analysis. These systems also comprise an instrument containing the analysis means and arranged to command and control the cartridge so that the latter may be simplified and designed to be used one time only and thrown away after use.
For instance, the document WO2009149115A1 discloses a cartridge for performing biochemical assays and having a deformable chamber. In the deformable chamber, some chemical operations are performed on a liquid containing the substances to be analyzed. Some air may be injected in the chamber to perform an agitation, thus increasing the pressure, and the valves of the deformable chamber shall be designed to withstand this pressure, to avoid any loss of liquid. It leads to either an increase of cost to design such secured valves, or to a loss of reliability of the test if some liquid is lost.
The document WO 2011048521 describes a system for performing DNA analysis which comprises an instrument operating a disposable cartridge that holds a liquid containing the biological sample. The cartridge is maintained onto an interface plate of the instrument by a vacuum force applied by the instrument onto the cartridge. The external face of the cartridge in contact with the interface plate is at least partially formed by an elastic membrane having a portion on which the vacuum is applied. To analyze the biological sample, a step of heating the liquid contained in said cartridge may be required. A chamber containing said liquid is arranged in the cartridge so that at least a wall of the chamber is formed by a portion of the membrane and a heater is arranged in the interface plate to contact said wall of the chamber and to heat the liquid. However, this solution leads to issues when air bubbles are contained in the liquid in the chamber. Indeed, during the heating, the air bubbles expand, so that the pressure increase inside the chamber, leading either to leaks in the circuit (resulting in a loss of the biological sample) or to a detachment of the cartridge from the instrument plate (resulting in an abortion of the analysis).
The document EP2182049A1 discloses a container for liquid reaction mixture, a reaction-promoting device using the same, and a method therefor. However, the container and device disclosed are complicated to manufacture and to use, as the device has a lower part and an articulated upper part, to clamp the container.
The document US2010104485A1 discloses a flow-through thermal cycling device comprising two opposite heaters in regards to a flexible chamber. A drawback of this device is the associated complexity of the heating device, as the flexible chamber shall be inserted between the opposite heaters.
The document US2006088931A1 discloses a thermal cycling system and vessel therefor, comprising two opposite heaters in regards to a flexible chamber. A drawback of this device is the associated complexity of the heating device, as the flexible chamber shall be inserted between the opposite heaters.